This report presents the
results of a study conducted for the National Highway Traffic Safety Administration
(NHTSA) to assess the highway safety effects of laws that prohibit open
containers of alcoholic beverages to be located in the passenger compartment
of motor vehicles operated on public roadways. These laws are commonly
referred to as Open Container laws.

Table 1.
Summary of Previous Open Container Laws in the First Four States
to Enact Laws to Conform with TEA-21 Requirements

State

Possession & Consumption

Passenger Area

All Alcoholic Beverages

All Occupants

All Public Highways

Primary Enforcement

Iowa

no

no

yes

no

yes

yes

Maine

no

no

yes

no

no

yes

Rhode Island

no

no

yes

no

yes

yes

South Dakota

yes

yes

no

yes

no

yes

Enforcement of the new conforming laws began on 1 July 1999 in Iowa and
South Dakota, on 1 October in Maine, and on 1 January 2000 in Rhode Island.
Data were obtained from agencies of the four states to identify effects
on traffic safety that might be attributable to changes in the states’
Open Container laws. The hypothesis of the evaluation is that conformance
with the Federal requirements is associated with a lower incidence of
alcohol-involved crashes.

Figure 1 presents the proportions of all fatal crashes that were alcohol-involved
in the four states during the six-month periods following the beginning
of enforcement of the states’ conforming laws, compared to data from the
same six-month periods in the previous year. The figure suggests that
the alcohol-involved proportion of fatal crashes in three of the four
states was lower during the first six months following enforcement of
conforming Open Container laws.7 Iowa had no apparent change;
however, the apparent change observed in the other three states is in
the direction expected if the laws had an impact; however, the declines
were not statistically significant (z test at 0.05).